Valve mechanism for internal-combustion engines.



V. P. COFFIN. VALVE MECHANISM FOR INTERNAL COMBUSTION ENGINES.

APPLICATION FILED PE B. 3, 1912.

2 SHEETS-BHEET 1.

[If @I II Patented Oct. 21, 1913.

M 5, j H e Z J 7 w o, 1P

Patented 0012111913.

3 SHEETS-SHEET 3.

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V. P. GOFPIN. VALVE MECHANISM FOR INTERNAL COMBUSTION ENGINES.

APPLICATION FILED rm. 3, 1912 1,076,551

XTE g VESTAL 1?. GOFEIN, 013' 331313, IDAHG.

Specification of Leiisrs 2s? A mamn iilsii February a, 1912! allwhom-2'15 may concern: to 1-: known that I, VEsTnL ciiizen of the UnitedSta as *2 refegrorl to nail: illus- Boiss, in the county of Ada anclState ml or oonvonsionol form. Polio, lmv invented new and use-fol. in:gross-n invention, I so movements in Valve Mechanism for inprovido 1nonv ylindsr of ternal Combustion Enginos, of which filo flis s in lqglins following is a specificminm, on can is anon {l ill to Thisinvention relates to internal com ciproosiory. also ll of inis invenbastion engines, and particularly to the Zion ssici Volvo, oam in illsClIiiVy lugs, 65

valve mechanism thereof, the prinmry obj sot of this invention belng toprovide a praot1- l l l l l l l I l rscipl'ocsting in o g cable. pistonvalve for controlling the l l i a l l l tion of 111*. 4 At. its with anor 1th parallel lo tbs diva i tlis ongi s piston 1 3 i' pro sidod .oohined, is oose tho mlniis w 5; 14; at different mission and exhaust ofgases to and from the oylinrioi', doing away entirely with tho o, s ll1% got o2. clap valve now in common use up n nsarly all typos enginestho use of the present invention ill A llI and durability of the engine,as n Whol is materially increased, and the sflioi noy nsiation ofpower." is 31.3?) pro- 3 7 mcroasecl, in tha the Volvo of l llzv ion notsubject to rapid i'hzm tors nil operates with growl, sw on linereofl $9111, it being proot'u 4. siihii'mwer served .1 valves now in ooimnon a;and also the valve praoticml noiso 1 ss:

Viioh the aboveand other objects in iew, tlm invomion consists in theconstruction, com; o. w n and arrangement of pu rizs, will behereinafter more fully (llfiCZfllKil.

illustrated in the accompanying drawings, glam", the and pointed out inthe claims hereunto apl exhaust Joni bopended k a o sxtcuiSillfil'illltlfill Y In the accompanying (lYyLWlDgSi Angora l l 0 .ELflown ii is a vertical s ctional view through one oyl- Jig, v ll mioiimyl'fmin each 2;? index '0 an engine, embodying the present 1' oihol' l;iiLion l9. invention. 2 is a vertical cross section it 7 taken on theline 2-2 of Fig. 1 looking my afluslly increased in toward the admissionanrl exhaust ports.

Fig. 3 is a horizontal section taken on tho the "as to 19 line 3-S ofFig. 1 when the piston is down, 0

Fig: 4 is a side elevation of 2]. portion of one: may: o n

cylinder, showing :1 {las ha bodies the admission and exhaust orifices.i 1 of vile gino pision 2, Fig: 5 is a side elevation of the some. lie,operates to suck 9 eferring to the drawings, 1 designates the cylinderof an internal combustion engins, 2 the piston working therein, 3 thewater japket, 4 the Waller space, 5 tin/a spark gilog hole, 8 the crankshaft, 7 fine oonneob 2 mother stroke, operl through the sxhaust011%13'95. ig the simian-1st cylinder is 1 1 @1- goal 1% loaning 3 l I ll l l 1 the extension which em l indotx: 1,.

l l a l 2 i l to the cylinder. The order of the corresponding ports isreversed in the valve, the inlet port 17 being located in a higher planethan the exhaust port 18.

In order to impart reciprocatory move ment to piston valve 11 andproperly time the same with respect to the ports of the cylinder, andthe movements of the en glue piston, 1 provide a cam 20 mounted on andrevolving with a rotary cam shaft 21. This cam is provided in one facewith a continuous or endless cam groove, embodying an outer loop 22 andan inner loop 23, the two loops intersecting, as shown at 2-4.Interposed between the cam and piston valve is a rock shaft 25 havingfast thereon. a lever arm which, at its extremity, carries a doublepointed shoe or dog 27 which traverses the convolutions of the camgroove 22-23, and is of sufiicient length and of proper shape to passthrough the intersecting portions at the point 24, without any liaeilityof the some finding its Way into the Wrong run of the cam groove.Another valve actuating arm or lever 28 is also mounted fast on the rockshaft 25, at the proper point, and is connected pivotally at 2-9 to oneend of the valve stem 30 of the piston valve, said stem being-connectedpiv otally, at 31, to the piston valve. The cam shaft 21 is geared tothe crank shaft 6, so as to rotate in the same direction therewith, andat the same speed as the crank shaft.

In operation, starting at the point (z of the cam groove, when the shoe27 is at the point a, the piston 2 is at the bottom limit of its strokeand the admission port has just closed, the combustion chamber beingthere fore filled with gas. In the revolution of the cam, when the point5 reaches the shoe 27, the engine piston 2 has reached the middie of itscompression stroke and both ports are closed. In moving from the point 5around the outer loop and across the intersection Z-i and up to thepoint 0, the piston is completing its compression and also its powerstroke, and when the point 0 reaches the shoe 27, the exhaust portstarts to 0 en. Moving on from the point e to point at the latter pointthe exhaust port is fully open. At the point e the exhaust port closes,and when the point f is reached, the admission port starts to open. .Atthe point "the admission port is fully open and remains open during themovement from back to a, at which last-narned point, the admission valvecloses and, ashefore stated, the engine piston 2 is at the bottom of itsstroke. This completes the cycle of movement of the cam 20, also'thepiston valve 11 and the engine piston 2. In Fig. 1, the pis ton isrising on the exhaust stroke, the exhaust port starting to close byreason of the piston valve 11 having just'started to move ownward; theexhaust port in the piston valve is fully closed at the instant when thetop of the piston closes the port. in the cylnder. I

Any suitable appliance may be used for delivering lubricating materialin the proper quantity to the piston valve 11, and as the jointoperation between the piston valve and its casing merely controls andalters the relation of ports, there can be no accumulation of carbon,such as is deposited upon the valves and valve seats of internalconibustion motors now in common use on auto mobiles and the like. Thisinsures smooth and easy operation of th valve, greatly incrr s the litethereof, gives increased i or power to the motor, and practiv with allvalve troubles now proper timing of the valve accomplished by theparticular form of m illustratedand described, as it will be observedthat the cam has two complete cycles of movement, during each revolutionthereof. l urthermore, the timing of the valve is all looked afterbefore the motor the factory, an thereafter it is impossible for thesame to out of timing,

another source of much annoyance, trouble, and in connection with thegasolene engines at present in use.

Vl hat is claimed is i l. in a fou cycha internal combustion enhiuation"with a cylinder, re-

p ston and nl-r shaft, of a chamber communicating with o h the medium ofindexhaust ports, a piston valve Working in s: d chamber and having indeendent'adm sion l exhaust ports able into and out of register withindependent admission and exhaustports letding into the cylinder, andmechanism for imparting a complete cycle of movement to the piston valveonce only in two revolutions of crank shaft.

:2. In a tour ole internal combustion engine, the coinhination with acylinder, re-

ciprocatory piston and crank shaft, of a,-

piston valve chamber communicating with the cylinder through the mediumof independent inle and exhaust ports, a piston valve WOllffl}; inschamber and having independent admission and exhaust ports movable intoand out of register with inde pendent admission and exhaust portsleading into the cylinder, the admission and exhaust ports ofthecylinder being arranged at different elevations and the correspondingports of the valve being also arranged at difierent elevations, andmechanism for imparting a complete cycle of movement of the pistonvalve. once only in .two revolutions of the crank shaft;

3. In a four-cycle internal combustion engins, the combination with acylinder, reciproca-tory piston and crank shaft, of a.

lot

piston valve chamber communicating with the cylinder through the mediumof independent inlet and exhailst ports, a piston valve Working in saidchamber and having independent admission and exhaust ports movable intoand out of register with independent admission and exhaust ports leadinginto the cylinder, and the admission and exhaust ports of the cylinderbeing arranged at different elevations and the corresponding ports ofthe valve being also arranged at different elevations but in the reverseorder to theports of the cylinder, the ports of the valve extendingthrough the valve body at an angle to each other,'while the cylinderports are correspondingl arranged to register therewith, and mec anismfor imparting a complete cycle of movement to the piston valve once onlyin two revolutions of the crank shaft.

In testimony whereof I afiix my signature in presence of two witnesses.

VESTAL P. COFFIN. Witnesses EDNA L. HICE, T. C. COFFIN.

copies of this patent may be obtained tor five cents each, by addressingthe Commissioner of Patents. Washington, D. G.

